Get<Paths<T>> fails when T has no properties that are known at compile time

[mwaibel-go]

Bug description

When T has no keys that are known at compile time, the Result of Paths<T> is not assignable to the second argument of Get.

Repro

https://www.typescriptlang.org/play/?#code/JYWwDg9gTgLgBDAnmApnA3nA4imAaOABQEMYALAZzgF84AzKCEOAciVQFo6UKYWBYAFBDgAOxgoodYgGM0AIQCuAcwA8AFTgoAHhNEATKumoA+DELhwwjMBQBc2XBoIlyFDSZNDqQA

import type { Get, Paths } from 'type-fest'

interface Bug<T extends {}> {
  props: Get<T, Paths<T>>
}

produces the error

Type 'Paths<T>' does not satisfy the constraint 'readonly string[] | LiteralStringUnion<ToString<_Paths<T, { maxRecursionDepth: 10; bracketNotation: false; }> | _Paths<T, { maxRecursionDepth: 10; bracketNotation: true; }>>>'.
  Type 'number | `${number}`' is not assignable to type 'readonly string[] | LiteralStringUnion<ToString<_Paths<T, { maxRecursionDepth: 10; bracketNotation: false; }> | _Paths<T, { maxRecursionDepth: 10; bracketNotation: true; }>>>'.
    Type 'number' is not assignable to type 'readonly string[] | LiteralStringUnion<ToString<_Paths<T, { maxRecursionDepth: 10; bracketNotation: false; }> | _Paths<T, { maxRecursionDepth: 10; bracketNotation: true; }>>>'.

Expected behaviour

I expect the code not to produce a compilation error. Specifically, Paths<T> should be a valid argument to Get<T, ⋅> for all T that are neither null nor undefined. (If I’m not mistaken, every other type in javascript does have properties).

In instances where T has a concrete type, the Bug::props type should be inferred.

interface Foo {
  key: number
}

let bar!: Bug<Foo>
let props = bar.props // number

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[sindresorhus]

What is the expected behavior?

[mwaibel-go]

I’m sorry for being unspecific. I’ve updated the issue description, @sindresorhus .